HADOOP-16299. [JDK 11] Build fails without specifying -Djavac.version=11

Signed-off-by: Takanobu Asanuma <tasanuma@apache.org>

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/LdapGroupsMapping.java

@@ -46,7 +46,6 @@
 import javax.naming.spi.InitialContextFactory;
 
 import com.google.common.collect.Iterators;
-import com.sun.jndi.ldap.LdapCtxFactory;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configurable;
@@ -270,8 +269,9 @@ public class LdapGroupsMapping
 
   public static final String LDAP_CTX_FACTORY_CLASS_KEY =
       LDAP_CONFIG_PREFIX + ".ctx.factory.class";
-  public static final Class<? extends LdapCtxFactory>
+
-      LDAP_CTX_FACTORY_CLASS_DEFAULT = LdapCtxFactory.class;
+  public static final String LDAP_CTX_FACTORY_CLASS_DEFAULT =
+      "com.sun.jndi.ldap.LdapCtxFactory";
 
   private static final Logger LOG =
       LoggerFactory.getLogger(LdapGroupsMapping.class);
@@ -314,7 +314,7 @@ public class LdapGroupsMapping
   private boolean useOneQuery;
   private int numAttempts;
   private int numAttemptsBeforeFailover;
-  private Class<? extends InitialContextFactory> ldapCxtFactoryClass;
+  private String ldapCtxFactoryClassName;
 
   /**
    * Returns list of groups for a user.
@@ -633,7 +633,7 @@ private DirContext getDirContext() throws NamingException {
     if (ctx == null) {
       // Set up the initial environment for LDAP connectivity
       Hashtable<String, String> env = new Hashtable<>();
-      env.put(Context.INITIAL_CONTEXT_FACTORY, ldapCxtFactoryClass.getName());
+      env.put(Context.INITIAL_CONTEXT_FACTORY, ldapCtxFactoryClassName);
       env.put(Context.PROVIDER_URL, currentLdapUrl);
       env.put(Context.SECURITY_AUTHENTICATION, "simple");
 
@@ -755,8 +755,18 @@ public synchronized void setConf(Configuration conf) {
     }
     SEARCH_CONTROLS.setReturningAttributes(returningAttributes);
 
-    ldapCxtFactoryClass = conf.getClass(LDAP_CTX_FACTORY_CLASS_KEY,
+    // LDAP_CTX_FACTORY_CLASS_DEFAULT is not open to unnamed modules
-        LDAP_CTX_FACTORY_CLASS_DEFAULT, InitialContextFactory.class);
+    // in Java 11+, so the default value is set to null to avoid
+    // creating the instance for now.
+    Class<? extends InitialContextFactory> ldapCtxFactoryClass =
+        conf.getClass(LDAP_CTX_FACTORY_CLASS_KEY, null,
+        InitialContextFactory.class);
+    if (ldapCtxFactoryClass != null) {
+      ldapCtxFactoryClassName = ldapCtxFactoryClass.getName();
+    } else {
+      // The default value is set afterwards.
+      ldapCtxFactoryClassName = LDAP_CTX_FACTORY_CLASS_DEFAULT;
+    }
 
     this.numAttempts = conf.getInt(LDAP_NUM_ATTEMPTS_KEY,
         LDAP_NUM_ATTEMPTS_DEFAULT);

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/security/TestLdapGroupsMappingBase.java

@@ -22,7 +22,6 @@
 import static org.apache.hadoop.security.LdapGroupsMapping.LDAP_CTX_FACTORY_CLASS_KEY;
 import static org.apache.hadoop.security.LdapGroupsMapping.LDAP_URL_KEY;
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.fail;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
@@ -36,6 +35,7 @@
 import javax.naming.directory.DirContext;
 import javax.naming.directory.SearchControls;
 import javax.naming.directory.SearchResult;
+import javax.naming.ldap.InitialLdapContext;
 import javax.naming.spi.InitialContextFactory;
 
 import org.apache.hadoop.conf.Configuration;
@@ -235,13 +235,10 @@ public Context getInitialContext(Hashtable<?, ?> env)
         assertEquals(expectedBindPassword, actualBindPassword);
       }
       if (contextToReturn == null) {
-        InitialContextFactory defaultFactory = null;
+        Hashtable<Object, Object> newEnv = new Hashtable<>(env);
-        try {
+        newEnv.put(Context.INITIAL_CONTEXT_FACTORY,
-          defaultFactory = LDAP_CTX_FACTORY_CLASS_DEFAULT.newInstance();
+            LDAP_CTX_FACTORY_CLASS_DEFAULT);
-        } catch (ReflectiveOperationException e) {
+        contextToReturn = new InitialLdapContext(newEnv, null);
-          fail("Could not initialize the default factory");
-        }
-        return defaultFactory.getInitialContext(env);
       }
       return contextToReturn;
     }

hadoop-project/pom.xml

@@ -2070,21 +2070,9 @@
               <additionalOptions>
                 <!-- TODO: remove -html4 option to generate html5 docs when we stop supporting JDK8 -->
                 <additionalOption>-html4</additionalOption>
-                <additionalOption>--add-exports</additionalOption>
-                <additionalOption>java.naming/com.sun.jndi.ldap=ALL-UNNAMED</additionalOption>
               </additionalOptions>
             </configuration>
           </plugin>
-          <plugin>
-            <groupId>org.apache.maven.plugins</groupId>
-            <artifactId>maven-compiler-plugin</artifactId>
-            <configuration>
-              <compilerArgs combine.children="append">
-                <arg>--add-exports</arg>
-                <arg>java.naming/com.sun.jndi.ldap=ALL-UNNAMED</arg>
-              </compilerArgs>
-            </configuration>
-          </plugin>
         </plugins>
       </build>
     </profile>